65664407161320 has 384 divisors, whose sum is σ = 229434949336320. Its totient is φ = 14971264000000.

The previous prime is 65664407161237. The next prime is 65664407161343. The reversal of 65664407161320 is 2316170446656.

It is a super-2 number, since 2×65664407161320² (a number of 28 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 338814445 + ... + 339008195.

It is an arithmetic number, because the mean of its divisors is an integer number (597486847230).

Almost surely, 2^{65664407161320} is an apocalyptic number.

65664407161320 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 65664407161320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (114717474668160).

65664407161320 is an abundant number, since it is smaller than the sum of its proper divisors (163770542175000).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

65664407161320 is a wasteful number, since it uses less digits than its factorization.

65664407161320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195177 (or 195162 counting only the distinct ones).

The product of its (nonzero) digits is 4354560, while the sum is 51.

The spelling of 65664407161320 in words is "sixty-five trillion, six hundred sixty-four billion, four hundred seven million, one hundred sixty-one thousand, three hundred twenty".